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The Atlantic Forest is an intensely fragmented and globally important ecological hotspot. In this context, the objective of this study was to analyze the landscape ecology and submit proposals for creating ecological corridors (ECs) in a Brazilian Atlantic Forest region. Landscape ecology metrics, based on the forest fragments map, were used for the analysis. Suggested corridors were based on least-cost path analysis, considering land use, declivity, permanent preservation areas (PPAs), and forest fragment sizes. Although the predominant class sizes in the study area are small fragments, landscape ecology analysis has shown good environmental quality for fragments larger than 100 ha that do not lose their central area, even for the largest edge distances. Four ECs were proposed, with an average length of 53.86 km, average width of 5.39 km, and average area of 28,786.32 ha. Land use conflicts showed that the fragments within the corridors were situated in a matrix dominated by grassland. PPAs within the proposed corridors were dominated by misused land and did not comply with environmental legislation. The proposed corridors were efficient in using the largest fragments, which have the least edge effect and provide necessary support for most wildlife. However, we emphasize that other factors can influence the delimiting of ECs; additional studies are required to obtain more effective ECs to connect habitats. The proposed methodology can be applied to other Brazilian and global ecoregion. [ABSTRACT FROM AUTHOR]

• A spatiotemporal approach was used to identify anthropogenic pressure on biomes. • The scenarios presented point to intensified pressure on biodiversity. • The region with the highest APIB values comprises 30% of the territory in all scenarios. Anthropogenic transformations, which have become intensified by land use and land cover changes and industrialization, have contributed to increased anthropogenic pressure on biodiversity. These disturbances contribute toward fragmentating habitats at different scales and putting species at risk, in addition to compromising the main biogeochemical cycles. To better understand the spatiotemporal dynamics of anthropogenic pressure on Brazilian biomes, this study sought to develop a composite index to identify and analyze the degree and distribution of anthropogenic-based pressure on biodiversity, and identify internally homogeneous and heterogeneous regions regarding the dynamics of this pressure in different scenarios. To that end, we carried out an analysis of the impact of select anthropogenic factors. Specifically, we analyzed future scenarios involving land use and land cover changes in line with the global structure Shared Socio-Economic Pathways (SSPs) and Representative Concentration Pathways (RCPs), according to the narratives SSP1/RCP 1.9, SSP2/ RCP 4.5 and SSP3/RCP 7.0. We used cluster and spatial analyses to determine the spatial dynamics of the index and, consequently, the regions most susceptible to anthropogenic pressure. The results demonstrate intensified pressure on biodiversity in areas that have already been subject to a considerable degree of disturbances, especially the Cerrado, Caatinga, and Atlantic Forest biomes. In all scenarios, the region with the highest average pressure index, i.e., Region 4, which has an average pressure index of 0.57, corresponds to 30% of Brazilian territory. This method made it possible to determine the level of pressure in each region and, subsequently, identify the regions that have been most affected by human actions in an effort to guide priority actions and local policies. However, it should be noted that this approach should be complemented with additional information, such as soil erosion, field recognition, and socioeconomic information. [ABSTRACT FROM AUTHOR]

• Sensitive taxa respond to deforestation in a non-linear manner. • Sensitive taxa more sensitive to catchment forest loss than to riparian forest loss. • Sensitive taxa offer early-warning signals of ecological damage from forest loss. • Brazil needs expanded forested riparian & catchment protections. Deforestation is a major threat globally, but especially in tropical regions because they are biodiversity strongholds and carbon storehouses. Some studies have reported changes in species richness and composition in lotic ecosystems with increased forest-loss in their catchment, presumably resulting from the replacement of sensitive taxa by more resistant or tolerant taxa. Also, sensitive taxa respond to deforestation in a non-linear manner and fish and macroinvertebrates have different sensitivities to landscape pressures. Therefore, it is useful to determine the effects of forest-loss on widespread sensitive or threshold taxa in aquatic ecosystems. We used Threshold Indicator Taxa Analysis (TITAN) to assess forest-loss and land use history impacts in 92 eastern Amazonian stream sites. We determined TITAN peak-change thresholds for fish at 1% and 6% of forest-loss at total-catchment and local-riparian spatial extents, respectively, and at 2% and 40% of land-use intensity change at total-catchment and local-riparian spatial extents, respectively. For macroinvertebrates, TITAN peak-change thresholds were 1% and 11% of forest loss at total-catchment and local-riparian spatial extents, respectively, and at 3% of land-use intensity change for both total-catchment and local-riparian spatial extents. Because of these thresholds, inherent ecoregional variability and key literature, we have three major recommendations. 1) Logging should be prohibited in riparian reserves that are at least 100-m wide on each side of headwater streams and in a network of catchments across all biomes and as many landscape types as possible. 2) An ecologically and statistically rigorous monitoring program with standard methods should be implemented to assess and regulate land uses better. 3) Conservation planning areas should consider aquatic biota as well as terrestrial biota. [ABSTRACT FROM AUTHOR]

• Land use, slope terrain, permanent preservation areas are essential to set ecological corridors. • AHP, LCP, and landscape metrics offer methodological support to the study. • AHP, based on mathematical weights, enhance empiric human perception in ecological functions. • The method to define ecological corridors contributes to policies of ecosystems protection. • This study is a scientific advance to connect habitats and can adapt to other ecoregions. The Brazilian Cerrado is a biodiversity hotspot of global importance; however, it is fragmented. The objective of this study is to identify suitable areas for ecological corridors (ECs) between two conservation units (CUs) located in the Espinhaço Range Biosphere Reserve (ERBR) in the Cerrado biome, Brazil, based on analytic hierarchy process (AHP), least-cost path (LCP) methods and landscape metrics. The methodology was based on the use of the AHP as a decision-making tool. Using the AHP, relative weights were attributed to the criteria used in the construction of land use, occupation, terrain slope and permanent preservation area (PPA) maps, which were then used for the delimitation of ECs in a GIS environment based on the LCP approach and landscape metrics. The results included a proposal of three ECs, listed as A, B and C, with areas of 34.28, 27.04 and 28.80 km2, respectively. The use of the AHP minimizes the subjectivity of the criteria used. The analyses identified that the ECs had similar habitat quality to that of the conservation units. EC-A presented the largest area of natural vegetation. EC-B presents comparable vegetation to that of EC-A and the shortest connection. EC-C contains the largest area of monoculture and is the least suitable option, given the choice of ECs. Additional studies using other spatial algorithms should be used to find paths to optimize distances and costs for establishing ECs in Brazil and/or other world ecoregions. [ABSTRACT FROM AUTHOR]